// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_COMPILER_OSR_H_
#define V8_COMPILER_OSR_H_

#include "src/zone/zone.h"

namespace v8 {
namespace internal {

    class OptimizedCompilationInfo;

    namespace compiler {

        class Frame;

        // Encapsulates logic relating to OSR compilations as well has handles some
        // details of the frame layout.
        class OsrHelper {
        public:
            explicit OsrHelper(OptimizedCompilationInfo* info);

            // Prepares the frame w.r.t. OSR.
            void SetupFrame(Frame* frame);

            // Returns the number of unoptimized frame slots for this OSR.
            size_t UnoptimizedFrameSlots() { return stack_slot_count_; }

            // Returns the environment index of the first stack slot.
            static int FirstStackSlotIndex(int parameter_count)
            {
                // TurboFan environments do not contain the context.
                return 1 + parameter_count; // receiver + params
            }

        private:
            size_t parameter_count_;
            size_t stack_slot_count_;
        };

    } // namespace compiler
} // namespace internal
} // namespace v8

#endif // V8_COMPILER_OSR_H_
